Multiple-jaw slip for engaging pipe



G. R. LIVERGOOD MULTIPLE JAW SLIP FOR ENGAGING PIPE April 21, 1925. 1,534,228

Fild Feb. 5', 1924 Patented Apr. 21, 1925.

UNITED STATES GERALD R. LIVERGOOD, 0F HOUSTON, TEXAS.

MULTIPLE-J'AW SLIP FOR ENGAGING PIPE.

Application filed February 5, 1924. Serial No. 690,832.

To all whom it may concern.

Be it known that I, GERALD R. Lrvnncoon, a citizen of the United States, residing at Houston, Harris County, Texas, have in vented a certain new and useful Improvement in a Multiple-J aw Slip for Engaging Pipe, of which the following is a specification.

My invention relates to an improvement in means for supporting pipe employed in well pumping and drilling operations. The device is particularly adapted for use in casing heads to support the tubing in pumping operations.

An object of the invention is to provide a single slip with a plurality of jaws adapted to enclose and support the pipe while the joints in the tubing are being screwed up or unscrewed while the pipe is being introduced into, or removed from the well.

Another object is to provide a single slip of this type wherein the jaws are so connected as to allow them to open at one side to be clamped around the pipe.

Another object is to provide a holding means for the jaws constituting the slip which will allow the jaws to automatically open when removed from their seat.

In supporting tubing in a well casing while the joints of said tubing are being screwed up or unscrewed, a plurality of slips of one or more jaws are ordinarily employed to raise and lower said slips from their seat, when it is desired to move the pipe. In my invention 1 contemplate the use of one slip alone, and to have a handle attached thereto in such manner that the jaws making up the slip will swing open automatically to release the pipe when the slip is raised.

Fig. 1 of the drawing shows a. top plan view; and Fig. 2 is a central vertical section of my slip in a casing head. Fig. 3 is a broken detail and Fig. 4 is a top plan view of the slip in open position.

In the drawing, the casing head of ordinary construction is shown at 1. It has the upper end recessed slightly to provide a seat at 2 for the flange 3 upon the tapered seat or bowl 4. Said bowl is made up of two parts, each of which is approximately semicylindrical at its outer face, and is tapered downwardly on its inner face to provide a seat 5 for the slip.

The slip constituting my invention is shown as made up of four jaws. Each jaw is arcuate in shape and has the inner face 6 toothed horizontally to engage the pipe in the usual manner. The outer face is smooth and tapered to fit the seat 5. The jaws are secured together at adjacent sides by means of connecting hinges, or keys 7, shown particularly in Fig. 3. The adjacent sides of the jaws are formed with vertical recesses 8 cylindrical in shape, extending from the upper end downwardly approximately half the length of the jaws as shown in Fig. 2. A slot or key way 9 extends from the opening 8 directly out to the edge of the jaw, said slot being flaredslightly outward to allow play of the key 7 thereon. The inner end of the key is formed with a longitudinal head 10 fitting loosely in the recess, said head being of such width that it may not pass through the opening or slot 9. Each of the keys are held downwardly in the recess by means of a threaded plug 11 fitting in the cylindrical upper end of each of the recesses 8. These keys are employed to connect each of the jaws to the adjacent jaw, except at one point 12, where the two adjacent jaws are adapted to swing apart from each other.

To allow for this swinging movement the handle is secured to the jaws so as to allow free play of the jaws upon the connecting keys. This is done by securing each of the end jaws 13 to the end of a sector shaped plate 14 by means of a set screw 15 fitting through an enlarged opening in the end of the plate 14, and screwed firmly within the jaw centrally thereof. The other end of the plate 14 is secured in a similar manner to the next adjacent jaw 16. The jaws are thus arranged in two pairs, each pair being made up of the jaws 13 and 16 and coupled together by means of plates 14 in the manner described.

Each set of two jaws is secured to a central plate 17. The plate 17 is arcuate in shape and is secured to the pins 18 by means of which the plate 14 is secured to the jaws 16, and directly above the plates 14. The pins 18 thus serve a double purpose of securing the plates 14 to the jaws 16 and also of securing the plate 17 to the inner ends of the plate 14. As shown in Fig. 1, the pins 18 extend through openings in the plate 17 at points spaced somewhat inwardly from the ends thereof, so as to allow the two inner jaws 16 to be spaced properly apart. The ends 19 of the plate 17 are extended upwardly to form cars 20 perforated to receive the outwardly curved ends of the bail 21.

It will be noted from Fig. 1 that the bail is pivoted at one side of the center of the slip, and its arrangement adjacent the hinged side of the slip allows the weight of the jaws to be somewhat over balanced toward the open side so that if the slip is raised from its seat, it will have a bearing on the side of the seat below the handle, thus tending -to allow the open side 12 to spread as it is drawn upwardly along the edge of the Seat, and thus release the pipe so that the slip may be readily removed. This action is automatic so that when the driller wishes to remove the slip from the pipe, it is only necessary to draw upwardly at the handle or bail 21, pulling the slip slightly toward the operator and the slip will open automatically and be easily removed from the pipe. When it is to be placed about the pipe, the driller places the lower end of the slip against the edge of the bowl and the slip will automatically open, due to the unbalanced position of theupper jaws, thus allowing the slip to drop downwardly into the seat and the circular shape of the bowl forming the seat will draw the jaws together forming the slip so that they will drop evenly into the seat and grip the pipe uniformly on all sides. It is contemplated that all of the plates 1% and 17 will be secured upon the pins 15 and 18 somewhat loosely due to the fact that the opening through the plates is larger than the external diameter of the pins. This fact, together with the loose fit of the connecting keys 7 will allow each jaw of the slip a certain freedom of adjustment so as to conform to the shape of the pipe, and obtain a firm grip thereon. Due to the fact that all of the jaws are connected together, they will drop uniformly into the seat and will grip the pipe on all sides evenly so as to overcome the tendency of the jaws on one side to cut the pipe.

The further advantages of this type of slip will be obvious to one skilled in the art, and while I have shown it as adapted particularly for use in casing heads, I wish it understood that it is not confined exclusively to this particular use further than is set forth in the following claims.

What I claim as new and desire to protect by Letters Patent is:

1. A device of the character described comprising a downwardly tapered bowl, a pipe-engaging means tapered to fit therein comprising a plurality of pairs of jaws toothed on their inner faces to engage the pipe, pivotal means to hold each of said jaws loosely to an adjacent jaw, connecting plates securing each pair of jaws at their upper ends, and a holding plate pivotally joining said connecting plates in the manner described.

2. A pipe supporting device comprising a tapered bowl, a slip adapted to fit therein comprising two pairs of toothed jaws each pair being hingedly connected together along their adjacent sides, a connecting plate joining each pair of jaws loosely together centrally of their upper ends, a holding plate joining the connecting plates loosely together at adjacent ends, and a handle on said holding plate.

3. A pipe engaging slip adapted to entirely surround the pipe comprising a plurality of jaws hingedly connected at their adjacent sides except at one side where said jaws are free to swing apart, connecting plates, pins centrally of the upper end of each jaw fitting loosely in the ends of said plates, and a holding plate joining said connecting plates loosely together.

4. A pipe engaging slip adapted to entirely surround the pipe, comprising a plurality of jaws hingedly connected together to open at one side, connecting plates loosely joining said jaws centrally of their upper ends and a holding means secured to said slip on the side away from the open side for the pur' pose described.

5. A pipe engaging slip comprising a plurality of jaws, keyways formed in the sides thereof, keys fitting loosely in said keyways to hinge said adjacent jaws together except on one open side of said slip, connecting plates joining adjacent pairs of jaws loosely together, a holding plate joining said connecting plates at the side of said slip away from said open side, and a handle on said holding plate.

6. A pipe engaging slip comprising a plurality of toothed jaws hinged loosely together at their adjacent sides except at one side of said slip where the slip may swing open, and a handle for said slip positioned thereon away from the open side of said slip, whereby the slip is unevenly balanced relative to said handle and will automatically open when elevated by said handle.

7. A slip adapted to fit within a tapered seat to engage a pipe, comprising a plurality of jaws hinged together at their adjacent sides and adapted to open at one side, plates at the upper ends of said jaws to which said jaws are loosely pivoted, and a handle on said plates secured toward the side away from the open side whereby the said jaws will automatically open when raised by said handle.

In testimony whereof I hereunto aflix my signature this 1st day of February, A. D.

GERALD R. LIVERGOOD. 

